January 23, 2012
Natural and Powerful Curry Derivative Protects Against Multiple Cancers
While plant-based formulations have been used to treat cancer for centuries, current treatments usually involve poisonous mustard gas, chemotherapy, radiation, and targeted conventional therapies which negatively affect a patient's long-term health. While traditional plant-derived medicines are safe, what are the active principles in them and how do they mediate their effects against cancer is perhaps best illustrated by curcumin, a derivative of turmeric used for centuries to treat a wide variety of inflammatory conditions.
Turmeric is a common ingredient in Indian food and yellow mustard. Its active ingredient is curcumin, which gives turmeric its yellow color.
Curcumin is a diferuloylmethane derived from turmeric (popularly called "curry powder") that has been shown to interfere with multiple cell signaling pathways, including cell cycle, proliferation, survival, invasion, metastasis and inflammation.
The activity of curcumin reported against leukemia and lymphoma, gastrointestinal cancers, genitourinary cancers, breast cancer, ovarian cancer, head and neck squamous cell carcinoma, lung cancer, melanoma, neurological cancers, and sarcoma reflects its ability to affect multiple targets.
Adding curcumin to human cells with the blood cancer multiple myeloma, Dr. Bharat B. Aggarwal of the University of Texas MD Anderson Cancer Center in Houston and his colleagues found, stopped the cells from replicating. And the cells that were left died.
Researchers at Rutgers, the State University of New Jersey, found that a combination of turmeric and phenethyl isothiocyanate (PEITC) was effective against prostate cancer. PEITC is abundant in a group of vegetables that includes cauliflower, cabbage, watercress, winter cress, broccoli, Brussels sprouts, kale, kohlrabi and turnips.
"The bottom line is that PEITC and curcumin, alone or in combination, demonstrate significant cancer-preventive qualities in laboratory mice, and the combination of PEITC and curcumin could be effective in treating established prostate cancers," Ah-Ng Tony Kong, a professor of pharmaceutics, said in a prepared statement.
Curcumin also inhibits the production of interleukin-8 (IL-8), a protein that attracts white blood cells to a particular site and leads to inflammation.
Controlling levels of these compounds "may have an important role in therapy for patients with malignant disease," Dr. Hideki Hidaka from Kumamoto University in Kumamoto, Japan and colleagues concluded.
If the spice component does indeed reduce IL-8 activities as the findings suggest, "curcumin is capable of working as a potent agent that reduces tumor promotion."
Tests in laboratory dishes show that curcumin made melanoma skin cancer cells more likely to self-destruct in a process known as apoptosis.
The same team has found that curcumin helped stop the spread of breast cancer tumor cells to the lungs of mice.
Bharat Aggarwal of the Department of Experimental Therapeutics at the University of Texas M.D. Anderson Cancer Center in Houston and colleagues treated three batches of melanoma cells, known as cell lines, with curcumin at different doses and for varying times.
University of Michigan researchers led by Ayyalusamy Ramamoorthy have discovered that curcumin acts as a disciplinarian, inserting itself into cell membranes and making them more orderly, a move that improves cells' resistance to infection and malignancy.
"The membrane goes from being crazy and floppy to being more disciplined and ordered, so that information flow through it can be controlled," said Ramamoorthy, a professor of chemistry and biophysics.
The research project melds Ramamoorthy's past with his current scientific interests. As a child in India, he was given turmeric-laced milk to drink when he had a cold, and he breathed steam infused with turmeric to relieve congestion. Now as researcher he is fascinated with proteins that are associated with biological membranes, and he uses a technique called solid-state NMR spectroscopy to reveal atom-level details of these important molecules and the membranous milieu in which they operate.
In a related line of research, Ramamoorthy's team is using the same methods to investigate the effects of curcumin on the formation of amyloids---clumps of fibrous protein believed to be involved in type 2 diabetes, Alzheimer's disease, Parkinson's disease, and many other maladies. In addition, the researchers are looking to see whether other natural products, such as polyphenols (compounds found in many plant foods that are known to have antioxidant properties) and capsaicin (a pain reliever derived from hot peppers), interact with membranes in the same way as curcumin.